Gluteal & Posterior Thigh Muscles

Question 1

Superficial gluteal muscles (4)?

Answer 1

1. Gluteus Maximus
2. Gluteus Medius
3. Gluteus Minmus
4. Tensor Fascia Lata

Question 2

Innervation of superficial gluteal muscles?

Answer 2

inferior gluteal n. = Gluteus Maximus

superior gluteal n =
Gluteus Medius
Gluteus Minmus
Tensor Fascia Lata

Question 3

Gluteus maximus functions (6)?

Answer 3

1. Extend thigh (main)
2. Abd thigh (upper 1/3)
3. Add thigh (lower 1/3)
4. Lateral rotation
5. Posterior pelvic tilt
6. Helps lock knee in extension via IT band

Question 4

Gluteus medius and minimus functions (5)?

Answer 4

1. Abd of thigh (entire muscle)
2. Flex thigh (ant fibers)
3. Medially rotate (ant fibers)
4. Extend thigh (post fibers)
5. Laterally rotate (post fibers)

Question 5

Trendelenburg sign & gait?

Answer 5

• glut med & min weakness
• pelvis falls upon lighting leg up
  -contralateral side

Question 6

Thigh deep fascia?

Answer 6

-tough fibrous sheath that invests thigh and glute m.
-thickens laterally to form IT band and invests TFL between its 2 layers and acts as a tendon for it.

Question 7

Tensor fascia lata? O, I, Function (5)?

Answer 7

O: anterior iliac crest
I: greys tubercle via ITB
Function:
1. Flex thigh
2. Abduct thighs
3. Med. rot. thigh
4. Anterior pelvic tilt
5. tenses ITB to support femur on tiba when standing

Question 8

What are the deep gluteal muscles (6)?

Answer 8

1. Piriformis
2. Superior Gemellus
3. Obturator internus
4. Inferior gemellus
5. Quadratus femoris
6. Obturator externus

Question 9

What is the nerve innervation of the 6 deep gluteal muscles?

Answer 9

1. Piriformis
2. Superior Gemellus
3. Obturator internus
4. Inferior gemellus
5. Quadratus femoris
6. Obturator externus

**all sacral plexus except obturator externus = lumbar plexus.

Question 10

What are the actions of the 6 deep gluteal muscles?

Answer 10

Lateral rotation & abduction of thigh:
1. Piriformis
2. Superior Gemellus
3. Obturator internus
4. Inferior Gemellus
Lateral rotation & adduction of thigh:
5. Quadratus femoris
6. Obturator externus

Question 11

Muscles in posterior thigh compartment (3)? And common nerve innervation?

Answer 11

hamstrings
-biceps femoris (lateral)
-semitendinous (medial)
-semimembranous (medial)

N= sciatic n but different branches innervate

Question 12

Biceps femora O, I, N, Function?

Answer 12

O:
long: tibial tuberosity
short: lineal aspera
I: lateral condyle of tibia & femur head
N:
long: tibial n
short: fibular/ peroneal n.
Func:
1. Extend thigh @ hip
2. Flex leg @ knee
3. Lat. rot of knee when knee flexed

Question 13

Semitendinous O, I, N, Function?

Answer 13

O: Ischial tuberosity
I: proximal medial shaft of tibia
N: tibial n
Function:
1. Extend thigh @ hip
2. Flex leg @ knee
3. Med. rot knee when knee flexed.

Question 14

Semimembranous N & function?

Answer 14

N: tibial n
Function:
1. Extend thigh @ hip
2. Flex leg @ knee
3. Med. rot knee when knee flexed.